GEOGRAPHICAL RANGE. 65 



nidae, of five longitudinal bundles of voluntary muscles, 

 with transverse striae, fixed to the scuta and terga, and 

 giving them powers of independent movement. In the 

 Lepadidae, the lower valves, or when such are absent, the 

 membranous walls of the capitulum, move with the scuta 

 and terga when opened or shut ; and the lower part of the 

 capitulum is separated by a moveable peduncle from the 

 surface of attachment ; in the sessile Cirripecles, the 

 lower valves are firmly united together into an immovable 

 ring, fixed immovably on the surface of attachment. I 

 will not compare the softer parts, such as the cirri and 

 trophi, of the Lepadidae with those of the Balanidae, as 

 my examination of this latter family is not fully com- 

 pleted : I will only remark, that there is a very close 

 general resemblance, more especially with the sub-family 

 Chthamalinae. 



Geographical. Mange; Habitats. — The Pedunculated 

 Cirripedes extend over the whole world ; and most of the 

 individual species have large ranges, more especially, as 

 might have been expected, those attached to floating 

 objects ; excepting these latter, the greater number in- 

 habit the warmer temperate, and tropical seas. Of 

 those attached to fixed objects, or to littoral animals, 

 it is rare to find more than three or four species in 

 the same locality. On the shores of Europe I know of 

 only three, viz., a Scalpellum, Pollicipes, and Alepas. 

 At Madeira (owing to the admirable researches of the 

 Rev. R. T. Lowe), two Paecilasmas, a Dichelaspis, and an 

 Oxynaspis are known. In New Zealand, there are two 

 Pollicipes and an Alepas, and, perhaps, a fourth form. 

 From the Philippine Archipelago, in the great collection 

 made by Mr. Cuming, there are a Paecilasma, an Ibla, 

 a Scalpellum, Pollicipes, and Lithotrya. Of all the 

 Lepadidae, nearly half are attached to floating objects, or 

 to animals which are able to change their positions ; the 

 other half are generally attached to fixed organic or in- 

 organic bodies, and more frequently to the former than 

 to the latter. Most of the species of Scalpellum are in- 



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